IntegraR0064

OK so I recently finished mass install of many suspension parts. This included J's camber joints in front, Nick's Penske 8300's with remote canisters and spherical bearing top mounts all around, new gendron front bar with bearing mounts and spherical bearing endlinks. I also took one endlink off in the rear since I plan to most likely run no rear bar but I want to experiment a bit.

I've got some noise that sounds like it's coming from the rear of the car. It's hard to explain but over bumps it sounds like there's a thing or two loose in the trunk. It sounds fairly similar to in my miata when the bolts on the battery tiedown in the trunk (which was metal) had loosened up enough that the battery tiedown had a little bit of play and was bouncing up and down against the metal trunk floor and the bolt holding it in. It sounds like a clunk, not a clang, and not a loud one, it's like it's a light impact. Over some bumps I'll get a few of the noises in series (again, as if something with just a little bit of play is bouncing back and forth). It seems much worse at low speed but I'm not sure if that's just because the road noise is quieter - and it's quiet enough that if I'm going over 50 mph with windows open or top down I can just barely hear it, but it's really pretty annoying during low speed driving or with windows closed, especially on bumpy roads. Also I'm worried that something actually is loose or is impacting something. I checked the bolts quickly and they seemed fine.

The front seems much better. I have a large lip coming out of my garage and I get one very quiet clunk from the front going over that (I also have a new gendron bar with the gendron heim joint endlinks), but otherwise the fronts seem to not make any extra noise over stock.

I'm looking for opinions on things to try or things to check. I'm new to installing high end coilovers so I don't know about anything extra that might be done with them as opposed to regular shocks.

In terms of more detail on what I modified in the rear, I put on the penskes, which have 700 lb 2.25"x6" hypercoils with a aluminum Genesis helper spring guide and a 4" zero rate helper spring from hypercoil. Ride height is a hair over 13" from hub to fender. 2 degrees of camber and 3/32" toe in. I used the stock M12 bolt to mount the bottom of the shock and put a M12 locknut and washer on it on the other side. I also took out the trunk trim piece by the spare tire and the trunk trim in front of the driver's side rear shock since I plan to have them out for the first couple local events so I can get to the shocks easily to try settings. The trunk is empty. I wrapped the canisters in 1/16" thick neoprene rubber then used two hose clamps and two each of normal canister rubber mounts to mount them to the top of the upper control arm in the rear. I also wrapped the canister lines with rubber to see if they were doing it and that wasn't it. The lines are also zip tied pretty tight to the control arms.

I have no helpers up front, but I do have helpers in the rear, so I'm starting to think maybe that's it. The springs have a fair amount of side to side play - the penske perches are just like a flat platform, they don't really cup the spring. In the rear, the helpers do extend a bit if I jack it up. I'm not using torrington bearings or thrust washers. I didn't grease any of the springs or perches - I read that that might be a good idea? I was also thinking about doing something with a thin piece of rubber on the ends of the springs potentially - right now there's no rubber anywhere. Or putting some tape around the ends maybe?

Is it possible that the rear sway bar is making the noise since it's only attached on one side? I know it's not hitting anything, but maybe since it's rotating inside the bushings that's making noise somehow...I dunno, I'm down to this kind of stuff.

Any ideas or guesses on what it might be, or things to test?

Thanks for any input.

PossumK

Since you get the noise in both the front and rear, it could be the spherical top mounts making noise, which is pretty common.

robinson

I have basically the same mounts you have since I copied nick. I can't hear any noise from the front, but the rears make a clicking/clanking sound that I can't get rid of. It's not the helper springs or springs at all as far as I can tell. My best guess is it's just the play in the spherical mount bearing.

IntegraR0064

Sorry, maybe I wasn't clear. I do not get the noise in the front.

Edit: At least I don't think so. There's such a racket going on.

IntegraR0064

Thanks for the reply. Do you just get one clank over a bump, or do you get continuous clanks as you drive down the road?

Maybe I'll take a video and see if the sound comes out right over the camera.

I fully attached the rear sway bar to rule it out, and as for the springs apart the right one and made sure there was absolutely no play in anything. I actually attached the spring/helper spring assembly together so it wouldn't have any play and used electrical tape to widen the radius of the ID of the perches to make sure that there was no side to side play. Then I greased the spring perches so there's no chance of the spring sticking. The assembly worked beautifully when I was done, I could shake the springs or do whatever I wanted and got no sound or movement other than rotation whatsoever. Then I buttoned everything up and took it for a test drive and the sound is just as bad as yesterday.

After some more driving around, there's clearly two different things doing a very similar sound, one on the right and one on the left. I'm starting to think it's the bearings. Did you use these ones too? http://secure.chassisshop.com/partdetail/COM12-T/

spdracerut

If it's a clicking noise, it's most likely from the CV joint due to the car being too low. Try raising it up to see what happens. Roughly 13" from wheel centerline to fender should be good. Or about 25.5" from ground to fender.

RonnieB

I am getting this problem with my SRC's. We have a thread in the suspension and brakes forum. Tried about everything and nothing fixes it. So I ordered T1R spacers for the axles that will be here this week. Hope that fixes it. I've tried playing with all the parts back there and the only time I can here any noise when the car is off the ground is when I play with the axel. I hear the exact same thing your taking about. I thought it might be the pillow mount but it wasn't after having it replaced.

robinson

Like I said, I copied Nick, so yes, I used those bearings, though, I don't think I got the tefflon coated ones. My sounds are continuous like yours.

marks_lude

Are the helper springs above or below the main spring in the rear?

If the helper springs are on the bottom, switch them around so they are on the top.

IntegraR0064

helper springs are on top already. I'll try and find the thread in the suspension forum about the half shaft spacers - any idea what it's called?

Thanks for the help so far!